Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Sender: Guenter Roeck <groeck7@gmail.com>
Subject: Re: [PATCH] watchdog: Add {min,max}_timeout sysfs nodes
To:     Juerg Haefliger <juerg.haefliger@canonical.com>,
        wim@linux-watchdog.org, linux-watchdog@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org,
        Juerg Haefliger <juergh@canonical.com>
References: <20210510131625.21506-1-juergh@canonical.com>
From:   Guenter Roeck <linux@roeck-us.net>
Message-ID: <695dfd0f-f090-653e-7580-e45484228781@roeck-us.net>
Date:   Mon, 10 May 2021 06:45:15 -0700
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.7.1
MIME-Version: 1.0
In-Reply-To: <20210510131625.21506-1-juergh@canonical.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 5/10/21 6:16 AM, Juerg Haefliger wrote:
> The valid range for the 'timeout' value is useful information so expose
> the min and max timeout values via sysfs.
> 
> Signed-off-by: Juerg Haefliger <juergh@canonical.com>
> ---
>   drivers/watchdog/watchdog_dev.c | 20 ++++++++++++++++++++
>   1 file changed, 20 insertions(+)
> 
> diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
> index 2946f3a63110..b84d53a79618 100644
> --- a/drivers/watchdog/watchdog_dev.c
> +++ b/drivers/watchdog/watchdog_dev.c
> @@ -525,6 +525,24 @@ static ssize_t timeout_show(struct device *dev, struct device_attribute *attr,
>   }
>   static DEVICE_ATTR_RO(timeout);
>   
> +static ssize_t min_timeout_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct watchdog_device *wdd = dev_get_drvdata(dev);
> +
> +	return sprintf(buf, "%u\n", wdd->min_timeout);
> +}
> +static DEVICE_ATTR_RO(min_timeout);
> +
> +static ssize_t max_timeout_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct watchdog_device *wdd = dev_get_drvdata(dev);
> +
> +	return sprintf(buf, "%u\n", wdd->max_timeout);

Makes sense, but please use sysfs_emit().

Guenter

> +}
> +static DEVICE_ATTR_RO(max_timeout);
> +
>   static ssize_t pretimeout_show(struct device *dev,
>   			       struct device_attribute *attr, char *buf)
>   {
> @@ -609,6 +627,8 @@ static struct attribute *wdt_attrs[] = {
>   	&dev_attr_state.attr,
>   	&dev_attr_identity.attr,
>   	&dev_attr_timeout.attr,
> +	&dev_attr_min_timeout.attr,
> +	&dev_attr_max_timeout.attr,
>   	&dev_attr_pretimeout.attr,
>   	&dev_attr_timeleft.attr,
>   	&dev_attr_bootstatus.attr,
>